Project Summary ? Abstract ? BRC1 The Biomarkers, Biomaterials, and Cellular Models Core is comprised of four laboratories that provide valuable human biospecimens and core services to internal and external Core users. The PKD Biomarkers Laboratory maintains a repository of serum, plasma, urine, and urinary exosomes from individuals with early- stage ADPKD that are being monitored in the Early PKD Observational Cohort (EPOC), a longitudinal clinical study. The repository also banks samples from at-risk siblings of these ADPKD participants, normal volunteers, and patients with established ADPKD that come to the PKD clinic at the University of Kansas Hospital. The current lack of sensitive and specific biomarkers for ADPKD is a major impediment in the development of new therapies. The Core will assist investigators in the discovery of effective biomarkers for diagnosing and monitoring the progression of early-stage ADPKD, a critical time before there is reversible damage to the kidneys. The Core will also perform in-house biomarker analysis of clinic samples to assist PKD investigators on the evaluation of therapeutic interventions. The PKD Biomaterials Laboratory maintains an established repository of a broad spectrum of human ADPKD biospecimens, including fixed and frozen cystic tissues, cyst fluids, and primary cultures of cyst epithelial cells. The Core has been critical for providing ADPKD biospecimens to academic and industry investigators for the past 14 years. The PKD Cellular Models Laboratory assists investigators in the use of human primary ADPKD cells, normal human kidney (NHK) cells and immortalized renal cell lines in carefully controlled in vitro assays. The Core has considerable expertise with in vitro models for the investigation of pathways involved in cyst epithelial cell proliferation, CFTR-dependent Cl- and fluid secretion, and in vitro cyst formation. The Core will continue to provide service and training to investigators on PKD cellular models to investigate mechanisms for cyst growth and for evaluating potential therapeutic compounds. The PKD Gene Targeting Laboratory assists in the generation of novel PKD reagents through gene- editing and assists Core users in gene-targeting approaches to test specific hypotheses. The Core will introduce specific mutations in PKD1 or PKD2 in immortalized cells from human collecting ducts, a prominent site for cyst formation in ADPKD. This enables investigators to examine the cellular response to a PKD mutation using isogenic normal and PKD mutant cell lines. The overall goal of the PKD Biomarkers, Biomaterials, and Cellular Models Core is to provide human ADPKD biospecimens and cellular models to assist investigators in translational research.